Spartanburg, South Carolina, is home to one of the largest privately owned chemical and textile research establishments in the world, Milliken & Company. The firm's innovative research that combines textiles and chemistry has now produced a thermoplastic composite called Tegris that is cheap, recyclable and tough. These properties make Tegris an attractive alternative to (or composite partner for) carbon fiber, and it's already proving to have wide ranging applications in the automotive, military and sporting industries.

Tough, cheap and 100 percent recyclable

With increasing demand for lighter and more fuel efficient vehicles using more environmentally-sustainable products, newer polypropylene-based products lay claim to being both green and cheap. Recent developments in additive and resin technologies have improved the performance, ease of production and range of applications for polymers such as polypropylene, particularly Tegris and a rival product named Pure from Dutch textiles manufacturer The Royal Lankhorst Euronete Group.

By collaborating with its clients, Milliken has been able to leverage its new technologies in interesting ways. One example is a carbon fiber/Tegris/carbon fiber sandwich that has equal stiffness to a carbon fiber-only structure, yet is 18 percent lighter, more damage tolerant and requires twice the energy to break. Another is an aluminum/Tegris/aluminum sandwich construction, which takes three times the energy to break.

The production process

Tegris starts out as a series of polypropylene (PP) films that form a tape yarn within a polymer matrix - for composite processing - before being woven into fabric. This is then pressed under heat and pressure to form a single piece approximately 0.005 inch (0.13 mm) that weighs just 0.02 lbs/sq.ft (0.11 kg/sq.m).

Sheet and plate is typically available in 0.125 inch, 0.250 inch and 0.500 inch thick sizes, so multiple layers are added depending on the required thickness. The NASCAR Aero splitters made from the material are typically 100 layers thick (1/2 inch or 12mm).

The outer layers are melted together to perform a similar function to that of resin in fiberglass products. From here, the sheet can be formed into a variety of shapes using heat and pressure, depending on the mold. The end result contains no fragment-producing glass, has high impact resistance and retains strength from around 180 degrees F down to -40F, as well as being easier on the production molds.

To put this into perspective, whilst having similar properties to carbon fiber, (the company claims 70 percent of the strength) Tegris won't shatter on impact, is approximately a tenth the cost, and is fully recyclable.

Applications

Tegris is already seeing use as protective armor by the U.S. military in its vehicles, primarily against IEDs. There's also such diverse applications as small watercraft, helmets, outdoor furniture and baggage.

Tumi, a high end luggage manufacturer which holds Tumi the exclusive rights for Tegris in the travel goods market, is already using the material in its new Tegra-Lite collection. This includes a range of packing cases and smaller carry-on baggage that claim enhanced durability, impact resistance and less weight. All very desirable attributes for baggage when traveling.

Tumi has exclusive rights to use Tegris in its new premium luggage range, Tegris-Lite

Another outfit that appreciates the lightness and toughness of the material is Riddell, makers of body armor for football players. Its Lightspeed Shoulder Pads are claimed to be the lightest in the business without compromising protection.

Motor racing has adopted Tegris in a number of ways - Powerstream's Aero splitter is one

In the automotive racing world, as mentioned, Tegris is being used in NASCAR racing for Aero splitters, as well as some door panels. Powerstream Industries has further developed the process to suit the equally harsh road racing environment, using CNC-machined pockets in a sheet of Tegris which is inlayed with high density foam and covered with a cap layer of Tegris that is then heat formed back into one piece, achieving a high level of rigidity.

Custom race Aero Splitter before the second layer of Tegris is added (machined recesses for hi-density foam clearly visible)

"Much of our development is to create advanced duplex composite panels to compete against carbon fiber," says Powerstream's Chris Meurett. "But with approximately 50 times the impact resistance."

Tegris can also be glued or threaded to accept mechanical fasteners. "We have done extensive testing with various adhesives designed for polypropylene and have found the bond unsatisfactory for our use," Meurett adds. "The very best way to bond Tegris to Tegris is through a consolidation process using heat and pressure on a platen press which when heated to the correct temperature essentially turn 2 pieces into 1."

Martin spent 17 years as road and track tester for Australian Motorcycle News and has raced motorcycles for over 40 years, picking up an Australian Championship in 1993 in the Unlimited Class Historic. An aircraft builder and experienced recreational pilot, he currently operates a test flight and maintenance facility, owns a Ducati 1000 and a Buell 1200 … and writes for Gizmag. All articles by Martin Hone

I think the disadvantage of highly toxic smoke in the case of fire outweigh any advantage it might offer.

Slowburn 17th February, 2012 @ 11:24 pm PST

@dawar: this does not use renewables and is from petrochemicals. Unless you are an oil sheikh, your application is misplaced , IMO. This should only be used where there is no other alternative. Housing applications are already using renewabled and recycled materials..why take a dozen steps backwards?

solutions4circuits 18th February, 2012 @ 01:14 pm PST

Most things that can be made with petrochemicals can also be made with plant based oils. Might take a bit more research.

VoiceofReason 19th February, 2012 @ 07:07 am PST

This is polypropylene. PP doesn't produce "highly toxic smoke." It does produce carbon dioxide and carbon monoxide, just any other burning polymer. There are also quite a few very promising developments in creating propylene from renewable feedstock, especially non-food crops.

Gadgeteer 19th February, 2012 @ 12:32 pm PST

If it is fully recyclable then the use of petrochemicals will be offset by its' continued recycling into affordable and lighter products.

Gary Richardson 19th February, 2012 @ 02:36 pm PST

In reality, recycling petrochemicals is primarily done with energy generated by petrochemicals. In some cases, burning the PP with energy recovery is actually favourable over recycling, because the non renewable energy used for recycling minus the energy you save by avoiding new PP production is higher.

Biocatalysis is a prime candidate for finding pathways for producing feedstock for PP out of renewable sources in the future however.

I'd like to know how flame resistant it is. Carbon fiber can easily turn a small vehicle or aircraft fire into an inferno with tiny strands of fiber left to float in the smoke making inhalation more dangerous to firefighters. I'd like to know if this will burn more slowly, so the fibers will be completely consumed instead of becoming airborne hazards, and also making firefighting easier.

Tiltrotortech 20th February, 2012 @ 02:26 pm PST

Burn Baby Burn.... PP is basically a modified petrochemical wax and therefore will burn nice and easily. Also not sure about its use as an armor system where the max temp is 180f, there are many vehicles that when parked up in their current locations would easily exceed that temp. Also what is the spall angle reduction when used as a spall liner?

MadMont 27th February, 2012 @ 07:05 am PST

I too can see potential here. Little more research and plant fiber could prove usable. How about complete auto, truck or machinery operator compartments. More accident protection, possible. How about base structure repairs with retained structural integrity, possible. I'll take a spherical house, come on hurricane.

MASTERMECH48 12th March, 2012 @ 07:34 pm PDT

Although this is interesting stuff, this product has been on the market for years. They just renamed it Tegris to enable a marketing campaign and coverage on the likes of Gizmag.